A high speed reciprocating probe system was constructed and used to investigate the perturbations of electrostatic probes on Hall thruster operations and on the measurement of local plasma parameters. Two regimes were investigated: inside the discharge chamber where the probe actively burned and at the exit plane where the probe experienced significant particle flux without burning. Experiments showed that in the interior of the thruster, significant probe material ablation occurred and severe

more »

... erturbations to thruster operation and plasma measurements could not be avoided, even with residence times as short as 0.5 s. At the exit plane of the thruster, no material ablation was observed, however, significant variations of the local measurements of electron temperature and number density were observed. Measurement variations were successfully avoided by the use of the high-speed probe, which kept the probe residence time to less than 0.5 s.